Reference may be made of the following U.S. Patents of interest: U.S. Pat. Nos. 3,869,023; and 4,024,930.
Various devices are presently in use for applying lubricating fluid to a particular part of a conveyor as the conveyor travels past the lubricating station in the course of normal operation. Generally, such automated lubrication systems include an air valve trip device periodically tripped by a portion of the conveyor system so as to actuate suitable apparatus for delivering lubricating fluid to the conveyor portion requiring lubrication. Thus, a lubrication sequence is initiated each time the particular conveyor portion is detected. In the installation of such prior art lubricating systems, the placement of the conveyor event detector and the lubricator output are set by the installer in accordance with a particular conveyor operational speed. In accordance with the particular conveyor speed, the installer takes into account the delay inherent in the lubrication apparatus between sensing the conveyor event and furnishing lubricant to the conveyor, and accordingly places the lubricating nozzle at the appropriate point downstream from the event detector.
In most applications of automated lubrication systems, lubrication sequences are not performed continuously. Instead, a timer device is often used to initiate a lubrication cycle, i.e., a number of lubrication sequences sufficient to service all lubrication points of the machine. In variable speed systems, where the amount of machine operation may vary widely in the interval established by the timer, timer use may result in either over-lubrication, with consequent waste of lubricant, or under-lubrication of the machine.
It is now desired to provide a more flexible automatic lubrication system for conveyors which will avoid both over-lubricating and under-lubricating a particular conveyor portion. In addition, it is desired to provide a conveyor lubrication system which will automatically compensate for varying conveyor speeds and which may be used to lubricate either constant speed conveyors, low or high speed conveyors, or variable speed conveyors. Furthermore, it is desired to enable the installer to install a lubricating system more readily by providing him with flexibility in locating the conveyor event detector and the lubrication delivery nozzle.